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Over the past decade the subject of informed consent has become increasingly important for general and forensic psychiatry. Viewed by many as the preeminent means by which psychiatric and other medical patients can secure their rights to full participation in treatment decision-making in therapeutic settings, informed consent has also gained general acceptance as an ethical and legal requirement for enrolling patients in human experimentation. The authors explore the many facets of this controversial issue.

The neurohypophysis of the opossum (Didelphis virginiana) was studied by electron microscopy in order to amplify Bodian's classic light microscopic observations in which he demonstrated a definite lobular pattern. The lobule of the opossum neurohypophysis is divided into three regions: a hilar, a palisade, and a septal zone. The hilar portion contains bundles of nerve fibers, the extensions of the hypothalamo-hypophyseal tract containing neurofilaments but few neurosecretory granules. In the opossum, pituicytes have a densely fibrillar cytoplasm. Herring bodies are prominent in the hilar region. They are large bodies packed with neurosecretory granules that have been described as end bulb formations of axons. From the hilar region, axons fan out into a palisade zone where the nerve terminals packed with neurosecretory granules, mitochondria, and microvesicles abut upon basement membranes. The neurosecretory granules are similar to those present in the neurohypophysis of other mammals, except for an occasional huge granule of distinctive type. Material morphologically and histochemically resembling glycogen occurs as scattered particles and as aggregates within nerve fibers. The septal zone, containing collagen, fibroblasts, and numerous small capillaries, is separated from the adjacent glandular tissue by a basement membrane.

The large oligotrich rumen protozoa Diplodinium ecaudatum and Ophryoscolex caudatus have been studied by electron microscopy during interphase and division. The structure of mature cilia is contrasted with that seen during their formation particularly in a tuft where development lags and is arrested. Here the shaft is only a few micra long and is composed of filaments that have circular cross-sections not in the typical circular arrangement. In their diameter and appearance the filaments are similar to filaments associated with the nuclei during division. The macronucleus has within it randomly directed filaments, while the micronucleus contains well aligned filaments and other arrangements typical of an intranuclear mitotic process. An extranuclear filament system is also present and is elaborated during division. The infraciliary filament system is particularly elaborate in these organisms. Filaments ranging from 14 to 22 mmicro have been observed with some tendency for a bimodal distribution in diameters of 15 and 21 mmicro. Formation of such filaments has been observed and consists of an initial orientation of very fine elements followed by filament formation. The observations are discussed in relation to filament involvements in cell movements. The concepts are discussed that filaments are metastable structures and that the transitions from one state to another are functionally significant.

Various aspects of the ultrastructure of the dividing nuclei in the large radiosensitive amoeba Pelomyxa illinoisensis are demonstrated. Evidence of nuclear envelope breakdown is presented, and membrane fragments are traced throughout metaphase to envelope reconstruction in anaphase and telophase. Annuli in the nuclear envelope and its fragments are shown throughout mitosis. During metaphase and anaphase some 15 to 20 mitochondria are aligned at each end of the spindle, and are called polar mitochondria. The radioresistant amoebae Pelomyxa carolinensis and Amoeba proteus do not have polar mitochondria, and Pelomyxa illinoisensis is unique in this regard. The shape of the P. illinoisensis interphase nucleoli differs from that in the two radioresistant species, and certain aspects of nucleolar dissolution in the prophase vary. Helical coils in the interphase nucleoplasm are similar to those in the radioresistant amoebae. A "blister" phase in the flatly shaped telophase nuclei of P. illinoisensis is described which is interpreted to be the result of a rapid nuclear expansion leading to the formation of the normal spherical interphase nuclei.

Uric acid is stored in the utriculi majores of the accessory sex glands of the German cockroach. Most of the uric acid is eliminated during copulation by being poured over the spermatophore. Mating appears to be an important means of excretion in this cockroach.

Objective: To determine the efficacy of combination therapy with cisplatin, doxorubicin, and cyclophosphamide alone or with radiotherapy for patients with extensive and those with limited unresectable thymoma.Design: Nonrandomized, prospective phase I-II trial.Setting: A Cooperative Oncology Group trial involving tertiary medical centers.Patients: Twenty of twenty-two patients with measurable, extensive or limited, unresectable thymoma were evaluable for response.Intervention: Patients were given cisplatin, 50 mg/m2 body surface area, doxorubicin, 50 mg/m2, and cyclophosphamide, 500 mg/m2, on day 1, with cycles repeated every 21 days until progression or until the maximally tolerated total doxorubicin dosage (for example, 450 mg/m2) was reached. Intravenous hydration with normal saline was administered during treatment courses. For responding patients with limited disease, 4500 cGy was administered to primary tumors after the second cycle of chemotherapy and before the initiation of the third cycle.Measurements and Main Results: Three complete and eleven partial remissions were seen in 20 evaluable patients, for a total response rate of 70% (95% CI, 46% to 88%). The median duration of remission was 13 months with three patients remaining continuously disease free for over 2 years. The median survival time of all eligible patients was 59 months (CI, 22 months to infinity). Four patients developed infections, including listerial and aseptic meningitides, mucocutaneous candidiasis, and cryptococcal pneumonia, that were indicative of a defect in cell-mediated immunity.Conclusions: Combination therapy with cisplatin, doxorubicin, and cyclophosphamide frequently produces objective remissions in patients with advanced thymoma. Further experience with this treatment regimen is warranted to clarify potential prognostic factors in patients with unresectable thymoma. [ABSTRACT FROM AUTHOR]